1. Field of the Invention
This invention relates to a wall construction assembly and, more particularly, to a bracketing system for assembling horizontal members to vertical studs.
2. Background Information
In a conventional wall frame assembly, a wall is constructed from a combination of horizontal members (or otherwise known as backing plates) affixed to vertical studs to form a frame structure onto which drywall or other types of wallboards are attached. Horizontal members and vertical studs are typically of a C-channel or U-channel flat strap stock variety, having a web connecting two flanges. Horizontal members can function as backing support by being installed transversely between vertical studs to provide enhanced lateral and vertical stability for the wall. Horizontal members can also function as reinforced backing to support heavy loads, such as from the mounting of heavy equipment on the wall to provide backing to anchor equipment. For example, when large medical equipment sinks are wall mounted in a hospital, a backing plate of sufficient load capacity is required to support it. Like bridging members, such backing plates are mounted transversely between vertical studs to provide enhanced stability to support dead loads and pull out loads.
Prior to the present invention, a horizontal member (referred herein alternately as bridging, backing or bridge backing member) would be affixed directly to the vertical studs, generally by means of attachment screws and/or weld. The horizontal member must be welded to account for poor design and construction tolerances. The direct assembly of horizontal members to vertical studs presented a number of problems.
First, though wall studs are typically installed at set intervals (e.g. 16 inch on center spacing), often there is variation in the spacing. Because of the variable spacing between studs, it is difficult to prefabricate (stock) bridge backing members to universally fit between the studs. Bridge backing members are manufactured in oversized stock lengths that must usually be cut to fit at the job site. The time and labor required to cut bridge backing members to custom fit the particular application greatly increase construction costs.
One attempt to overcome the problem of fitting a bridging or backing member between variably spaced studs is disclosed in U.S. Pat. No. 4,717,101 to Harrod, which teaches an adjustable backing board. The invention disclosed by Harrod is comprised of two interfitted rectangular channel pieces, telescoped together, with one piece being slideably mounted within the larger channel such as to be adjustable therein. Similarly, U.S. Pat. No. 4,658,556 to Jenkins teaches a system of expandable and retractable backing spans for fitting between studs. Both patents are directed to adjustable backing members, rather than to a bracketing system for mounting standardized backing members, and both require complex engineering to make the backing members adjustable.
A second problem with attaching bridge backing members directly on vertical studs is that, because the backing members are cut from stock channels, the backing members have no end surfaces that can be fastened to the vertical studs. As a consequence, in order to attach a bridge backing member between two studs, it is generally necessary to cut the ends of the flanges on the backing member so that the web of the bridge backing member can be fastened over the vertical studs. That is, the flanges must be cut to fit between the studs, such as to leave corresponding sections of the web on either end to overlap with the sides of the vertical studs. For example, n U.S. Pat. No. 1,867,449, Ecket et al. teaches a bridging member for positioning between studs variably spaced apart, in which the ends of the bridging member must be cut inwardly to provide a securing plate for attaching to the studs. The drawback of having to custom cut each bridge backing member in this way to fit between the studs is the increase in construction time and cost.
A third problem with the direct assembly of bridge backing members to vertical studs is that it often resulted in cosmetic problems because it created bulges in the wallboard, which required additional labor and material to correct by finishing over the uneven surface of the wall. The problem resulted from the fact that when the backing member is mounted directly on the studs, the web of the backing member sits over the side flanges of the studs which, plus the buildup of the screw, created an uneven surface. In order to eliminate this problem of an uneven surface resulting from the direct attachment of the screw on the stud surface, a backing member would have to be mounted flush with the sides of the vertical studs.
U.S. Pat. No. 5,189,857 to Herren et al. teaches a flush mount bridging and backing plate having a traverse end plate at one end of the channel and a Z-shaped tongue at the opposite end of the channel. The tongue fits between the two flanges of a stud, thereby allowing the backing plate to be mounted flush with the sides of the stud. The end plate and tongue provide end tabs so that the backing plate can be mounted directly onto the studs' web without having to cut the flanges on the backing plate as described above. However, one major disadvantage of backing plates having prefabricated end tabs is that it is still required to mount directly to the studs without the ability to adjust to uneven stud layout. Because of the variable spacing between studs, stock backing members having prefabricated end tabs do not always fit between studs that are variably spaced apart. If in a particular application the studs are too wide or too narrow apart, such stock backing plates having prefabricated end tabs do not fit. Furthermore, it is more costly to manufacture backing plates with Z-shaped end tabs that are not adjustable.
In sum, the standard practice in the art is to mount backing members directly onto and over studs, which results in the disadvantages described above. For the foregoing reasons, there is a need for a bracketing system that can mount horizontal bridge backing members with vertical studs. There is a need for a cost-effective installation method for a bracketing system that can mount stock bridging or backing members between variably spaced studs without the need to cut each individual member to fit between the studs. There is a need for a bracketing system that can mount bridge backing members without having to cut the flanges of the members to create end tabs for mounting on the studs. There is a need for a bracketing system that can allow for a bridge backing member to mount flush with the stud, so as to eliminate cosmetic unevenness in the wall structure. The claimed invention avoids the above problems and provides significant savings in material and labor costs (e.g. scrap (leftover) materials can be used as bridge backing between studs and on said bracketing system).